/Engine/Plugins/Runtime/RigVM/Source/RigVMDeveloper/Public/RigVMCompiler/RigVMAST.h
Returns an obsolete block for unmanaged expression
[FRigVMBlockExprAST](API\Plugins\RigVMDeveloper\RigVMCompiler\FRigVMBlockExprAST) * GetObsoleteBlock ( bool bCreateIfMissing )